1. Field of the Invention
The present invention relates to a process for assembling a carriage for driving a marking apparatus on at least one guiding member, as well as to a corresponding marking apparatus.
Within the meaning of the invention, the generic term xe2x80x9cmarking apparatusxe2x80x9d designates any apparatus for making a mark on the surface of a piece, whether it be by printing, deformation or by removal of matter on or from this surface.
2. Description of the Related Art
As is known, a marking apparatus comprises a frame supporting a mechanism for driving a marking tool, which may in particular be a pneumatic stylus or an engraving head. This drive mechanism conventionally comprises an element fixed with respect to the frame, provided with raised edges on which two guide bars are disposed. A first drive carriage is mounted to slide on the latter and is itself provided with two additional bars, which are perpendicular to the afore-mentioned first pair of bars and are intended to receive a second drive carriage to which the marking tool is fastened.
Thanks to the use of this so-called xe2x80x9ccrossed carriagexe2x80x9d drive mechanism, the marking tool is able to move in two directions perpendicular to each other, with respect to the frame.
The process of assembling each carriage on the guide bars which receive it consists firstly in making at least one bore in this carriage, then in arranging in each bore at least one self-lubricating bearing, for example by adhesion or by force-fit. This assembly thus constituted is then mounted to slide on the guide bars.
However, this known process of assembly presents certain drawbacks. In effect, it is accompanied by an extremely meticulous operation for positioning this carriage with respect to the self-lubricating bearing, which involves a particularly precise machining of the said bores. This process therefore involves lengthy and costly manufacture.
It is an object of the invention to overcome these drawbacks by proposing a process which, while ensuring a precise assembly of the drive carriage on its guide member, is simple and rapid to carry out and dispenses with any expensive machining operation.
To that end, it relates to a process for assembling a carriage driving a marking apparatus on at least one guide member, the carriage being secured to a bearing allowing the carriage to slide on the guide member according to the process at least one opening is made in the carriage adapted to receive the bearing and this bearing is interposed between the walls of the opening and the guide member An intermediate ring is arranged around the guide member. The at least one opening is made with transverse dimensions substantially greater than those of the intermediate ring. The carriage is placed in the precise position that it must occupy and an intermediate space is thus defined between the walls of the opening and the opposite outer periphery of the ring. The intermediate space is filled with a polymerizable resin and, by polymerization of this resin, a sleeve is formed between the walls of the opening and at least a part of the outer periphery of the intermediate ring.
The invention also relates to a process for assembly a carriage driving a marking apparatus on at least one guide member the carriage is to a bearing allowing the carriage to slide on the guide member. At least one opening is made in the carriage adapted to receive the bearing and this bearing is interposed between the walls of the opening and the guide member. The opening is made with transverse dimensions substantially greater than those of the guide member and the carriage is placed in the precise position that it must occupy and an intermediate space is thus defined between the walls of the opening and the opposite outer periphery of the guide member. The intermediate space is filled with a polymerizable resin and, by polymerization of this resin, a sleeve is formed between the walls of the opening and at least a part of the outer periphery of the guide member.
Finally, the invention relates to a marking apparatus, comprising a frame, a marking tool and at least one carriage driving the marking tool. The carriage is mounted to slide with respect to at least one guide member. The guide member is housed in a corresponding opening made in the carriage, and a bearing for slide is interposed between the guide member and the opposite walls of the corresponding opening. The bearing comprises a sleeve which is formed by a resin polymerizable in the solid state and which extends to the vicinity of the walls of the opening.